Retainer for trolleys



FIG. 1 is a rear, top, and right perspective view of the retainer for trolleys showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a right elevational view thereof; and,

FIG. 6 is a left elevational view thereof. 

CLAIM The ornamental design for a retainer for trolleys, as shown and described. 